1. Field of the Invention
The present invention relates to a semiconductor device including a semiconductor chip connected by the wire bonding.
2. Description of the Related Art
Japanese Patent Laid-Open No. 2000-216188 and Japanese Patent Laid-Open No. 11-67808 are cited as a conventional wire bonding technique for the semiconductor device.
For example, in a wire bonding method described in Japanese Patent Laid-Open No. 2000-216188, a bonding wire is used to connect between an electrode included in the semiconductor chip and a lead. In this method, the wires are positioned by bending the wires in their middle by means of pins to prevent contact between the wires.
In a technique described in Japanese Patent Laid-Open No. 11-67808, wires are inclined in a sealing resin flowing-direction to prevent contact between adjacent wires during mold resin sealing.
However, the recent demand for high performance and small packaged semiconductor chips has called for reduction in a pitch between pads. The wiring has become complex because of the SIP (Single In-Line Package) structure. Particularly, as the number of wirings between the semiconductor chips has increased, the distance between the adjacent wires has become narrower under the restriction on the arrangement of the semiconductor chips. Since this causes a concern for short-circuit of the wires or the like, it is necessary to extend a distance between the wires.
Since the techniques described in Japanese Patent Laid-Open No. 2000-216188 and Japanese Patent Laid-Open No. 11-67808 are a technique for connecting a bonding pad of the semiconductor chip with a lead, the arrangement on the lead side is less restricted. For example, in the technique described in Japanese Patent Laid-Open No. 2000-216188, the leads are positioned with the center-to-center distance between the leads wider than that between the bonding pads to widen the pitch between wires.
On the other hand, when the bonding pads are connected to each other, the arrangement of the bonding pads imposes a restriction. Specifically, the bonding pads are arranged in line on the semiconductor chip. Thus, when the semiconductor chips whose sizes are different from each other, or the semiconductor chips in which the distances between the bonding pads are different from each other are connected to each other, the wire connected between the bonding pads is angled, and therefore the distance between the adjacent wires becomes narrower.
The present invention has been made in consideration of the above circumstance, and the technique for connecting between the bonding pads of the semiconductor chips prevents contact between the wires.